Substrate treatment device

ABSTRACT

A device for the treatment of substrates has a fluid container filled with a treatment fluid and at least one substrate receiving device. A lifting device is provided for lifting and lowering the at least one substrate receiving device out of and into the treatment fluid. The lifting device is arranged laterally at the container and has parts that are positioned above the container and the treatment fluid. A vapor suction device with a suction channel is provided for exhaustion of vapors in an area in which parts of the at least one lifting device are located above the treatment fluid. In the area above the treatment fluid, a plate is provided having an opening to which the suction channel is connected.

BACKGROUND OF THE INVENTION

The invention concerns a device for the treatment of substratescomprising a fluid container filled with a treatment fluid, wherein atleast one substrate receiving device and one lifting device for thelifting and lowering of the substrate receiving device is provided, thelifting device arranged laterally at the container and having partspositioned above the container and above the treatment fluid.

Devices of the aforementioned kind are known from DE 44 13 077 A1 and DE195 46 990 A1 of the applicant of this present patent application andare also described in the German patent applications DE 196 16 402.8, DE196 15 969.2, DE 196 37 875.3 and DE 195 37 879.2 of the same applicant,which have not been published as of the filing date of this application.In these devices, the lifting device is positioned laterally at thefluid container. The parts of the lifting device that support thesubstrate receiving devices immersed in the treatment fluid, protrudeinto an area above the tank and above the treatment fluid. Because thetreatment fluid contains chemicals, the vapors of these chemicals arepresent above the surface of the treatment fluid and, in particular,also in the area of the lifting device. Especially when the liftingdevice is enclosed by a housing, these vapors accumulate in the area ofthe lifting device and inside the housing.

The components of the lifting device that are being immersed into thetreatment fluid, are coated or covered by a material, for example,plastic, to prevent the contact of the components of the lifting device,commonly comprised of stainless steel or aluminum, with the treatmentfluid and the chemicals contained therein that otherwise would corrodethe stainless steel or aluminum materials. However, it is not possiblethat all components of the lifting device outside of the treatment fluidare coated with a protective layer, such as for instance, connectionsthat require a precise assembly with small tolerances or components thatare movable relative to one another. At least these parts and surfacesof the lifting device are exposed to the vapor and corroded by it.Therefore, the service life of these lifting devices is short.

From the documents JP 4-157724 A2, JP 1-2655519 A2 and JP 6-84876 A2devices are known wherein at least one fluid container is completedenclosed in a housing into which clean air is blown in from the top andis removed at the bottom or laterally.

From the documents JP 3-258380 A2, JP 7-273079 A2 and 5-129268 A2devices are furthermore known that are provided with an air removal orvapor removal suction device.

Based on this, the object of the invention is to improve a device forthe treatment of substrates of the aforementioned kind in a way that alonger service life for the lifting device is achieved and the device isprotected from chemical vapors.

SUMMARY OF THE INVENTION

The object of the invention is inventively solved by providing a vaporsuction device that exhausts the developing vapors, especially in anarea in which parts of the lifting device are located above thetreatment fluid. This prevents that the aggressive vapors can attack thelifting device and its precisely manufactured and cooperating componentsand functional elements. To avoid repetition concerning the embodimentof the lifting device and its components and functions, reference ismade to the application DE 195 46 990 A1 and DE 196 37 875.3 that areincorporated by reference into the present patent application (thelatter application has not been published as of the filing date of thisapplication).

According to a preferred embodiment of the invention, the lifting deviceis contained within housing. This housing provides the suction area forthe vapor suction device and encloses the aforementioned area. The useof a housing particularly increases the risk of damaging chemical vapornot only ingressing and remaining inside the housing, but also ofaccumulation of the chemical vapor and increased concentration withinthe housing. In this way, the components of the lifting devices insidethe housing are corroded even more and the service life will decreaseeven more. This is prevented with the features of the invention.

An especially advantageous embodiment of the invention is that the vaporsuction device removes the vapors above the surface of the treatmentfluid, thus directly at the location where they develop. The removaltakes place in the aforementioned area of the lifting device more orless directly above the surface, thus, in particular, in the area abovethe surface of the treatment fluid, where the housing is positioned.

It is advantageous to provide a planar plate for vapor removal, arrangedin the area of the lifting device above the treatment fluid, the platebeing connected by an opening to a suction channel of the vapor suctiondevice. To this end, it is ensured that the vapors are exhausted at thelocation where they develop, i.e. directly above the surface of thetreatment fluid. Because the plate in this embodiment is positionedabove the surface of the treatment fluid and, advantageously, with onlya small distance from the treatment fluid surface, the volume to beexhausted remains small, which, in regard to the expensive reprocessingfacilities and procedures necessary for such exhausted air contaminatedby vapors, is especially advantageous.

According to another very advantageous embodiment of the invention, aseparating element is provided above the surface of the treatment fluidthat separates the area of the lifting device from the area for thetreatment of the substrates. This embodiment is also beneficial inregard to the vapor suction device having to exhaust only a limitedvapor volume while preventing intake of air from areas outside thelifting device area that would increase the volume to be exhausted.

The separating element is preferably embodied as a stay that projectsdownwardly from the plate provided in the area of the lifting device, inparticular, from the side or edge of the plate that faces the inside ofthe fluid container, and is immersed in the treatment fluid. To thisend, a restricted, small volume is defined and contained for the vaporexhaustion in the area of the lifting device with the result that thevapor suction volume remains small.

The vapor exhausted by the vapor suction device is preferably suppliedto a reprocessing facility, where the damaging vapors are removed fromthe air and neutralized.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention is described in the following with the aid of preferredembodiments with reference to the figures. It is shown in:

FIG. 1: a schematic cross-section of a device for the treatment ofsubstrates,

FIG. 2: a schematic partial cross-section of a device shown in FIG. 1with the area of the lifting device in top view, and

FIG. 3: a cross-section along the section line III—III shown in FIG. 2.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIG. 1 shows a schematic cross section of a device for the treatment ofsubstrates, as shown and described in the German patent application 19637 875.3 of the same applicant, which has not been published as of thefiling date of this application. To avoid repetition concerning theembodiment of this device, reference is made to this application, whichis incorporated by reference into the present patent application. Theparts of the device shown in FIG. 1 that are necessary for thedescription and explanation of the vapor suction device, are howeverdescribed in the following section.

The device shown in FIG. 1 is comprised of a removable hood 2 arrangedabove a fluid container 1 and a substrate receiving device 3 forsupporting a substrate package 4 inside the fluid container 1. Thesubstrate receiving device 3 is connected by mounting elements 5, 6 anda support arm 7 to a lifting device 8 that is surrounded by a housing 9.

The lifting device 8 with differential lift, shown in FIG. 1, isdescribed in DE 195 46 990 A1 of the same applicant. Reference istherefore made to this document which is incorporated by reference intothe present patent application to avoid repetition concerning thisembodiment.

A housing 9 for the lifting device 8 has a part that is partiallyprotruding past the fluid container 1 to surround also the area 10 ofthe lifting device situated above the fluid container 1 to which areconnected the support arms 7.

The treatment fluid in the fluid container 1 contains chemicals thatrise as vapors from the surface of the treatment fluid. For example, acleaning or rinsing agent commonly contains a small amount ofhydrochloric acid that is necessary for dissolving contaminants orparticles still adhering to the substrates, e.g., semiconductor wafers.In this case, vapors of hydrochloric acid are forming above the fluidsurface. These vapors are not critical in the area of the hood 2,because they are dispersed and suctioned away together with the gasintroduced into the hood 2 for the drying process based on the Marangoniprinciple. To avoid repetition concerning these processes and features,reference is made to DE 44 13 077 A1 or DE 195 46 990 A1 of the sameapplicant. These chemical vapors are not critical, even without the hood2, because a device of this kind is usually installed in a clean roomwith a steady laminar flow from ceiling to floor that would remove thechemical vapors forming in the area of the surface of the treatmentfluid.

Very different conditions exist in area 10 of the lifting device abovethe surface of the treatment fluid. In particular, when the liftingdevice 8 is enclosed by a housing 9—but even without the housing 9—thesevapors will come into contact with the lifting device 8 and itscomponents. Whereas the support arms 7 and all components inside thefluid container 1 are coated with a protective layer against aggressivechemicals, this is not possible outside the fluid container 1,especially for components of the lifting device that are movablerelative to one another and/or precision components that require aprecise assembly with small tolerances. To avoid repetition, referenceis again made to DE 195 46 990 A1.

To prevent the contact of, in some cases, very aggressive chemicalvapors, e.g., vapors of hydrochloric acid, with the components of thelifting device 8, that are preferably made of stainless steel oraluminum and are not or cannot be coated with a protective layer, avapor suction device is inventively provided and described in thefollowing with the aid of FIGS. 2 and 3.

FIGS. 2 and 3 only show the area of the fluid container 1 that containsan area for the fluid treatment and an area 13 with support arms 7. FIG.2 particularly shows the support arms 7 and their arrangement in thefluid container 1. To avoid repetition, reference is again made to DE 4413 077 A1 and DE 195 46 990 A1.

As particularly shown in FIG. 3, the treatment fluid flows through aninlet tube 15 into the fluid container 1 and is discharged throughoverflow slots 16 along the upper edge of the fluid container 1.

On the top of the container, a plate 17 is provided in the area 13 forthe support arms 7. It is hollow and contains an opening 18, into whichthe suction channel 19 opens that is connected by an elbow fitting 20 toa non-represented vacuum source. Hereby, the vapors that are forming inthe area of the lifting device 8 above the fluid surface, are exhaustedtherewith. Because the plate 17 is positioned only a small distance fromthe fluid surface, the air volume to be exhausted with the chemicalvapors contained therein remains small.

From the elongate side or edge 21 of the plate 17 that faces the insideof the fluid container 1, a separating element 22, shaped as a stay,protrudes downwardly from the plate 17 and is immersed in the treatmentfluid. The air volume above the fluid surface in the area of the liftingdevice 8 and/or the housing 9 between the plate 17 and the fluid surfaceis thus also laterally delimited, so that no air from other areas of thefluid surface is suctioned in and the volume to be exhausted remainssmall and limited.

The invention has been disclosed with the aid of preferred embodiments.However, persons skilled in the art may be able to implement variousalterations, designs and modifications without departing from the gistof the invention. It is, for instance, possible to provide a suctionchannel 20 not only at one but several points of the suction plate 17.Furthermore, the present invention is not limited to the embodiments ofthe described treatment and lifting devices for substrates.

The specification incorporates by reference the entire disclosure ofGerman priority documents 196 45 425.5 of Nov. 4, 1996, as well as ofInternational Application PCT/EP97/05408 of Oct. 1, 1997.

The present invention is, of course, in no way restricted to thespecific disclosure of the specification and drawings, but alsoencompasses any modifications within the scope of the appended claims.

What is claimed is:
 1. A device for the treatment of substrates (4),said device comprising: a fluid container (1) filled with treatmentfluid (3); at least one substrate receiving device (3); a lifting device(8) for lifting and lowering said at least one substrate receivingdevice (3) out of and into the treatment fluid; said lifting device (8)arranged laterally at said container (1) and having parts that arepositioned above said container (1) and the treatment fluid; a vaporsuction device (17-22) comprising a suction channel (19) for exhaustionof vapors in an area (10) in which parts of said at least one liftingdevice (8) are located above the treatment fluid; and a housing (9),wherein said lifting device (8) and said parts located above thetreatment fluid are surrounded by said housing (9).
 2. A deviceaccording to claim 1, wherein said vapor suction device (17-22) isprovided above the surface of the treatment fluid in said area (10) forexhausting vapors present above the surface in said area (10).
 3. Adevice according to claim 1, further comprising a separating element(22) separating said area (10) above the treatment surface from asurface area below which the treatment of the substrates takes place. 4.A device according to claim 3, wherein said separating element (22) is avertical stay projecting downwardly from said plate (17) and immersed inthe treatment fluid.
 5. A device according to claim 1, wherein in saidarea (10) a plate (17) is provided having an opening (18) to which saidsuction channel (19) is connected.